Fibers for artificial hair, method for producing same, and hair accessory

ABSTRACT

A fiber for artificial hair, having a base fiber, a metal ion, and an antistatic agent, in which the metal ion and the antistatic agent are present in at least a part of a surface of the base fiber, the metal ion is at least one selected from the group consisting of a silver ion, a zinc ion, and a copper ion, a content of the metal ion is 5.0×10−5 to 1.0×10−2% by mass based on the total mass of the fiber for artificial hair, the antistatic agent is at least one selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent, and a content of the antistatic agent is 0.001 to 1% by mass based on the total mass of the fiber for artificial hair.

TECHNICAL FIELD

The present invention relates to a fiber for artificial hair, a method for producing the same, a headdress article, and the like.

BACKGROUND ART

Fibers for artificial hair (fibers used for artificial hair) can be used for headdress articles. In Patent Literature 1 below, a technique of treating a base fiber using a fiber treating agent is disclosed.

CITATION LIST Patent Literature

Patent Literature 1: Japanese Unexamined Patent Publication No. 2002-285470

SUMMARY OF INVENTION Technical Problem

Since consumers using headdress articles do not frequently wash the headdress articles in some cases, the scalp or the headdress article cannot be maintained cleanly, and bacteria may grow, which causes malodor or the like. Therefore, fibers for artificial hair used for headdress articles are required to have antibacterial activity.

Furthermore, from the viewpoint of suppressing generation of static electricity, it is conceivable to use an antistatic agent in a fiber for artificial hair in order to impart antistatic property. However, according to the finding of the present inventors, when the antistatic agent is used, tactile sensation such as stickiness and roughness may be deteriorated in some cases, and from the viewpoint of preventing a user from feeling uncomfortable, the fiber for artificial hair is required to be excellent in tactile sensation such as stickiness and roughness.

An object of an aspect of the present invention is to provide a fiber for artificial hair having excellent antibacterial activity and antistatic property while suppressing stickiness and roughness. An object of another aspect of the present invention is to provide a headdress article having such a fiber for artificial hair. An object of still another aspect of the present invention is to provide a method for producing such a fiber for artificial hair.

Solution to Problem

An aspect of the present invention relates to a fiber for artificial hair, having a base fiber, a metal ion, and an antistatic agent, in which the metal ion and the antistatic agent are present in at least a part of a surface of the base fiber, the metal ion is at least one selected from the group consisting of a silver ion, a zinc ion, and a copper ion, a content of the metal ion is 5.0×10⁻⁵ to 1.0×10⁻²% by mass based on the total mass of the fiber for artificial hair, the antistatic agent is at least one selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent, and a content of the antistatic agent is 0.001 to 1% by mass based on the total mass of the fiber for artificial hair.

Another aspect of the present invention relates to a headdress article having the above-mentioned fiber for artificial hair.

Still another aspect of the present invention relates to a method for producing a fiber for artificial hair, the method including a step of bringing a base fiber into contact with a treating agent containing a metal ion and an antistatic agent, in which the metal ion is at least one selected from the group consisting of a silver ion, a zinc ion, and a copper ion, a content of the metal ion is 3.0×10⁻⁴ to 3.0×10⁻²% by mass based on the total mass of the treating agent, the antistatic agent is at least one selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent, and a content of the antistatic agent is 0.005 to 4% by mass based on the total mass of the treating agent.

Advantageous Effects of Invention

According to an aspect of the present invention, a fiber for artificial hair having excellent antibacterial activity and antistatic property while suppressing stickiness and roughness can be provided. According to another aspect of the present invention, a headdress article having such a fiber for artificial hair can be provided. According to still another aspect of the present invention, a method for producing such a fiber for artificial hair can be provided.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described in detail.

The expression “A or more” of a numerical value range means A and a range of more than A. The expression “A or less” of a numerical value range means A and a range of less than A. With regard to a numerical value range described stepwise in the present specification, the upper limit value or the lower limit value of the numerical value range at a certain stage can be optionally combined with the upper limit value or the lower limit value of the numerical value range of another stage. With respect to a numerical value range described in the present specification, the upper limit value or the lower limit value of the numerical value range may be substituted with the values shown in Experimental Examples. The expression “A or B” may include either A or B or may include both of them. Unless particularly stated otherwise, the materials described as examples in the present specification can be used singly or in combination of two or more kinds thereof. In a case where a plurality of substances corresponding to each component in a composition is present, unless particularly stated otherwise, the content of each component in the composition means the total amount of the plurality of substances present in the composition. The term “step” means not only an independent step, but even in a case where a step cannot be clearly distinguished from another step, the step is included in the present term as long as the predetennined action of the step is achieved. The term “(meth)acrylic acid” means at least one of acrylic acid and methacrylic acid corresponding thereto.

A fiber for artificial hair of the present embodiment has a base fiber (fibrous base), a metal ion, and an antistatic agent, and the metal ion and the antistatic agent are present in at least a part of a surface of the base fiber. In the fiber for artificial hair of the present embodiment, the metal ion is at least one (hereinafter, referred to as “metal ion A”) selected from the group consisting of a silver ion, a zinc ion, and a copper ion, the content of the metal ion A is 5.0×10⁻⁵ to 1.0×10⁻²% by mass based on the total mass of the fiber for artificial hair, the antistatic agent is at least one (hereinafter, referred to as “antistatic agent A”) selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent, and the content of the antistatic agent A is 0.001 to 1% by mass based on the total mass of the fiber for artificial hair.

The fiber for artificial hair of the present embodiment has excellent antibacterial activity and antistatic property while suppressing stickiness and roughness. The “stickiness” means stickiness of the fiber surface sensed when the fiber is touched. The “roughness” means roughness of the fiber surface sensed when the fiber is touched. The fiber for artificial hair of the present embodiment can have excellent antibacterial activity against Staphylococcus aureus as excellent antibacterial activity.

The fiber for artificial hair of the present embodiment can be used as artificial hair and can also be used in order to obtain artificial hair. The fiber for artificial hair of the present embodiment may be a fiber obtained after a stretching treatment, or may be an unstretched fiber.

Examples of the base fiber material include a vinyl chloride-based resin, a (meth)acrylic resin (excluding a resin corresponding to the vinyl chloride-based resin), a polyolefin-based resin (excluding a resin corresponding to the vinyl chloride-based resin or the (meth)acrylic resin), a polyester-based resin (excluding a resin corresponding to the vinyl chloride-based resin, the (meth)acrylic resin, or the polyolefin-based resin), and a polyamide-based resin, and a mixture thereof may be used. For example, the base fiber may be an embodiment containing a vinyl chloride-based resin, an embodiment containing a polyester-based resin, an embodiment containing a polyolefin-based resin, and the like. The base fiber may contain a mixture of a vinyl chloride-based resin and a component that can form a polymer alloy with the vinyl chloride-based resin. Examples of the component that can form a polymer alloy with the vinyl chloride-based resin include an ethylene-vinyl acetate copolymer (EVA), an acrylonitrile-butadiene rubber (NBR), a thermoplastic polyurethane (TPU), a polyester-based thermoplastic elastomer (TPEE), a methyl methacrylate-butadiene-styrene resin (MBS), an acrylonitrile-butadiene-styrene resin (ABS), an acrylonitrile-styrene copolymer (AS), and polymethyl methacrylate (PMMA).

From the viewpoint of easily obtaining excellent flame retardation and the viewpoint of excellent processability for a headdress article, the base fiber preferably contains at least one selected from the group consisting of a vinyl chloride-based resin, a polyolefin-based resin, and a polyester-based resin, and more preferably includes a vinyl chloride-based resin. The vinyl chloride-based resin is a polymer having a structural unit derived from vinyl chloride, and is a polymer having vinyl chloride as a monomer unit. The vinyl chloride-based resin can be obtained by bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, or the like, and is preferably obtained by suspension polymerization from the viewpoint of excellent initial colorability of fibers or the like.

Examples of the vinyl chloride-based resin include a homopolymer of vinyl chloride (homopolymer, polyvinyl chloride) and copolymers of vinyl chloride and other monomer, and a mixture thereof may be used. Examples of the copolymers of vinyl chloride and other monomer include a copolymer of vinyl chloride and vinyl esters (such as a vinyl chloride-vinyl acetate copolymer and a vinyl chloride-vinyl propionate copolymer); a copolymer of vinyl chloride and a (meth)acrylic acid compound (such as (meth)acrylic acid and a (meth)acrylic acid ester) (such as a vinyl chloride-butyl acrylate copolymer and a vinyl chloride-2-ethylhexyl acrylate copolymer); a copolymer of vinyl chloride and olefins (such as a vinyl chloride-ethylene copolymer and a vinyl chloride-propylene copolymer); and a vinyl chloride-acrylonitrile copolymer. The vinyl chloride-based resin may not have a structural unit derived from a (meth)acrylic acid compound. In the copolymer, the content of the monomer different from vinyl chloride can be determined according to required qualities such as molding processability and fiber characteristics. From the viewpoint of excellent processability for a headdress article, the vinyl chloride-based resin preferably includes at least one selected from the group consisting of a homopolymer of vinyl chloride, a copolymer of vinyl chloride and a (meth)acrylic acid compound, and a vinyl chloride-acrylonitrile copolymer, and more preferably includes at least one selected from the group consisting of a homopolymer of vinyl chloride and a vinyl chloride-acrylonitrile copolymer.

The content of the vinyl chloride-based resin in the base fiber may be 50% by mass or more, 70% by mass or more, 90% by mass or more, 95% by mass or more, 98% by mass or more, or 99% by mass or more, based on the total mass of the base fiber. The base fiber may be an embodiment composed of only a vinyl chloride-based resin (substantially 100% by mass of the base fiber is a vinyl chloride-based resin).

The (meth)acrylic resin is a polymer having a structural unit derived from a (meth)acrylic acid compound (such as (meth)acrylic acid or (meth)acrylic acid ester), and is a polymer having a (meth)acrylic acid compound as a monomer unit.

Examples of the polyolefin-based resin include polyethylene and polypropylene.

Examples of the polyester-based resin include polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene-2,6-naphthalate, and polymethylene terephthalate.

Examples of the polyamide-based resin include nylon 6, nylon 66, nylon 11, nylon 12, nylon 6/10, and nylon 6/12.

From the viewpoint that the stretch ratio can be made small in order to obtain a fiber for artificial hair with a finer fiber degree, and that luster is less likely to be generated in the fiber for artificial hair after a stretching treatment, the average fineness of the base fibers at the time of being unstretched is preferably 300 decitex or less, and more preferably 200 decitex or less.

The metal ion A is present in at least a part of the surface of the base fiber, and for example, is attached to at least a part of the surface of the base fiber. The metal ion A can be used as an antimicrobial component. The metal ion A may be contained in the metal salt that is present in at least a part of the surface of the base fiber. The metal ion A preferably includes a silver ion from the viewpoint of easily improving the antibacterial activity.

The metal ion A may form a composite body (for example, a metal salt of a polymer compound) with a polymer compound, and the composite body of the metal ion A and the polymer compound may be present in at least a part of the surface of the base fiber. By the metal ion A forming the composite body with the polymer compound, the metal ion A is likely to be attached to the surface of the base fiber. The metal ion A may form, for example, a complex with the polymer compound.

The polymer compound can have structural units derived from various monomers. Examples of monomers that provide the polymer chain include (meth)acrylic acid, a (meth)acrylic acid ester (such as poly(alkylene glycol) alkyl ether (meth)acrylate (poly(ethylene glycol) methyl ether (meth)acrylate, etc.) and butyl (meth)acrylate), a vinyl compound (such as vinylimidazole (1-vinylimidazole, etc.) and vinylpyridine (4-vinylpyridine, etc.)), ethylene, butadiene, 2,3-dichloro-1,3-butadiene, 1-chloro-1,3-butadiene, isoprene, and styrene. The polymer compound may have a structural unit derived from a (meth)acrylic acid ester (may have a (meth)acrylic acid ester as a monomer unit), or may have a structural unit derived from a (meth)acrylic acid ester and a structural unit derived from a vinyl compound (may have a (meth)acrylic acid ester and a vinyl compound as monomer units).

The content of the metal ion A is 5.0×10⁻⁵% by mass or more based on the total mass of the fiber for artificial hair from the viewpoint of obtaining excellent antibacterial activity. The content of the metal ion A is 1.0×10⁻²% by mass or less based on the total mass of the fiber for artificial hair from the viewpoint of obtaining an excellent roughness suppressing effect of the fiber for artificial hair. The content of the metal ion A is the total amount of the silver ion, the zinc ion, and the copper ion.

The content of the metal ion A, the content of the silver ion, the content of the zinc ion, or the content of the copper ion is preferably 8.0×10⁻⁵% by mass or more, 1.0×10⁻⁴% by mass or more, 2.0×10⁻⁴% by mass or more, 3.0×10⁻⁴% by mass or more, 4.0×10⁻⁴% by mass or more, 5.0×10⁻⁴% by mass or more, 7.0×10⁻⁴% by mass or more, 8.0×10⁻⁴% by mass or more, 1.0×10⁻³% by mass or more, 3.0×10⁻³% by mass or more, 4.0×10⁻³% by mass or more, 4.5×10⁻³% by mass or more, 5.0×10⁻³% by mass or more, 6.0×10⁻³% by mass or more, 7.0×10⁻³% by mass or more, or 8.0×10⁻³% by mass or more, based on the total mass of the fiber for artificial hair, from the viewpoint of easily obtaining excellent antibacterial activity.

The content of the metal ion A, the content of the silver ion, the content of the zinc ion, or the content of the copper ion is preferably 8.0×10⁻³% by mass or less, 7.0×10⁻³% by mass or less, 6.0×10⁻³% by mass or less, 5.0×10⁻³% by mass or less, 4.5×10⁻³% by mass or less, 4.0×10⁻³% by mass or less, 3.0×10⁻³% by mass or less, 1.0×10⁻³% by mass or less, 8.0×10⁻⁴% by mass or less, 7.0×10⁻⁴% by mass or less, 5.0×10⁻⁴% by mass or less, 4.0×10⁻⁴% by mass or less, or 3.0×10⁻⁴% by mass or less, based on the total mass of the fiber for artificial hair, from the viewpoint of easily obtaining excellent tactile sensation (such as a stickiness suppressing effect or a roughness suppressing effect) of the fiber for artificial hair.

The content of the metal ion A, the content of the silver ion, the content of the zinc ion, or the content of the copper ion is preferably 8.0×10⁻⁵ to 8.0×10⁻³% by mass, 2.0×10⁻⁴ to 7.0×10⁻³% by mass, 4.0×10⁻⁴ to 6.0×10⁻³% by mass, 5.0×10⁻⁴ to 5.0×10⁻³% by mass, 1.0×10⁻³ to 5.0×10⁻³% by mass, or 3.0×10⁻³ to 5.0×10⁻³% by mass, based on the total mass of the fiber for artificial hair, from the viewpoint of easily achieving both the antibacterial activity and the tactile sensation at a high level.

The fiber for artificial hair of the present embodiment may have the antistatic agent A that is present in at least a part of the surface of the base fiber. By using the antistatic agent A, the antistatic property can be improved. For example, the antistatic agent A is attached to at least a part of the surface of the base fiber. As the antistatic agent A, a compound not containing the metal ion A can be used.

From the viewpoint of easily obtaining excellent antistatic property since the antistatic agent is likely to be present in at least a part of the surface of the base fiber (at the time of production of the fiber for artificial hair, the stability of a fiber treating agent described below is likely to be enhanced), the antistatic agent A is at least one selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent.

Examples of the cationic antistatic agent include a quaternary ammonium salt, a guanidine compound, an imidazoline compound, and a pyridinium compound. The guanidine compound can include at least one selected from the group consisting of guanidine and a salt thereof.

Examples of the quaternary ammonium salt include tetraalkylammonium chloride, tetramethylammonium sulfate, tetraalkylammonium hydrosulfate, trialkylammonium chloride, and aryltrialkylammonium chloride. Examples of the guanidine salt include a guanidine hydrochloride salt and a guanidine phosphate salt. From the viewpoint of easily obtaining excellent antibacterial activity and antistatic property while suppressing stickiness and roughness, the antistatic agent A preferably includes at least one selected from the group consisting of a quaternary ammonium salt and a guanidine compound.

Examples of the non-ionic antistatic agent include a polyhydric alcohol (for example, polyalkylene glycol such as polyethylene glycol), a fatty acid ester of polyhydric alcohol, and an alkylene oxide polymer (for example, a copolymer of propylene oxide and ethylene oxide). From the viewpoint of easily obtaining excellent antibacterial activity and antistatic property while suppressing stickiness and roughness, the antistatic agent A preferably includes at least one selected from the group consisting of a polyhydric alcohol and an alkylene oxide polymer, and more preferably includes at least one selected from the group consisting of polyalkylene glycol and a copolymer of propylene oxide and ethylene oxide.

The weight average molecular weight of polyalkylene glycol (for example, polyethylene glycol) may be in the following range from the viewpoint of easily obtaining excellent antibacterial activity and antistatic property while suppressing stickiness and roughness. The weight average molecular weight may be 100 or more, 200 or more, 300 or more, 400 or more, 500 or more, 550 or more, or 600 or more. The weight average molecular weight may be 2000 or less, 1500 or less, 1000 or less, 800 or less, 700 or less, 650 or less, or 600 or less. From these viewpoints, the weight average molecular weight may be 100 to 2000, 300 to 1000, or 550 to 650.

From the viewpoint of easily obtaining excellent antistatic property since the antistatic agent is likely to be present in at least a part of the surface of the base fiber (at the time of production of the fiber for artificial hair, the stability of a fiber treating agent described below is likely to be enhanced because the deposition of a sulfur-containing compound is easily suppressed), at least one selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent preferably includes an antistatic agent not containing a sulfur atom.

The fiber for artificial hair of the present embodiment may have an anionic antistatic agent, an ionic liquid, or the like as the antistatic agent that is present in at least a part of the surface of the base fiber.

Examples of the anionic antistatic agent include a sulfonate salt, a sulfate ester salt, and a phosphate ester salt (for example, a polyoxyalkylene alkyl ether phosphate salt).

As the ionic liquid, a liquid compound salt composed of only ions (cation and anion) can be used. Examples of the cation of the ionic liquid include an ammonium ion, an imidazolium ion, a pyridinium ion, a pyrrolidinium ion, a pyrrolinium ion, a piperidinium ion, a pyrazinium ion, a pyrimidinium ion, a triazolium ion, a triazinium ion, a quinolinium ion, an isoquinolinium ion, an indolinium ion, a quinoxalinium ion, a piperazinium ion, an oxazolinium ion, a thiazolinium ion, and a morpholinium ion. Examples of the anion of the ionic liquid include a halogen-based ion, a boron-based ion, a phosphorus-based ion, and a sulfonate anion. As the ionic liquid, an amine salt containing ions having an amino group can be used.

The content of the antistatic agent A is 0.0010% by mass or more based on the total mass of the fiber for artificial hair from the viewpoint of obtaining excellent antistatic property. The content of the antistatic agent A is 10% by mass or less from the viewpoint of obtaining an excellent stickiness suppressing effect of the fiber for artificial hair. The content of the antistatic agent A is the total amount of the cationic antistatic agent and the non-ionic antistatic agent.

The content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 0.005% by mass or more, 0.01% by mass or more, 0.015% by mass or more, 0.02% by mass or more, 0.03% by mass or more, 0.05% by mass or more, 0.1% by mass or more, 0.15% by mass or more, 0.19% by mass or more, 0.2% by mass or more, 0.25% by mass or more, 0.3% by mass or more, 0.35% by mass or more, 0.4% by mass or more, 0.5% by mass or more, 0.6% by mass or more, 0.8% by mass or more, or 0.9% by mass or more, based on the total mass of the fiber for artificial hair, from the viewpoint of easily obtaining excellent antistatic property.

The content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 0.9% by mass or less, 0.8% by mass or less, 0.6% by mass or less, 0.5% by mass or less, 0.4% by mass or less, 0.35% by mass or less, 0.3% by mass or less, 0.25% by mass or less, 0.2% by mass or less, 0.19% by mass or less, 0.15% by mass or less, 0.1% by mass or less, 0.05% by mass or less, 0.03% by mass or less, 0.02% by mass or less, 0.015% by mass or less, 0.01% by mass or less, or 0.005% by mass or less, based on the total mass of the fiber for artificial hair, from the viewpoint of easily obtaining an excellent stickiness suppressing effect of the fiber for artificial hair.

From these viewpoints, the content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 0.005 to 0.9% by mass, 0.01 to 0.9% by mass, 0.01 to 0.5% by mass, 0.02 to 0.5% by mass, 0.02 to 0.4% by mass, 0.02 to 0.3% by mass, 0.03 to 0.3% by mass, or 0.05 to 0.2% by mass, based on the total mass of the fiber for artificial hair.

The content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably in the following range with respect to 100 parts by mass of the metal ion A.

The content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 1.0×10² parts by mass or more, 1.1×10² parts by mass or more, 2.0×10² parts by mass or more, 2.2×10² parts by mass or more, 3.0×10² parts by mass or more, 4.0×10² parts by mass or more, 4.4×10² parts by mass or more, 5.0×10² parts by mass or more, 6.0×10² parts by mass or more, 6.3×10² parts by mass or more, 7.0×10² parts by mass or more, 1.0×10³ parts by mass or more, 1.1×10³ parts by mass or more, 2.0×10³ parts by mass or more, 2.2×10³ parts by mass or more, 3.0×10³ parts by mass or more, 4.0×10³ parts by mass or more, 4.4×10³ parts by mass or more, 5.0×10³ parts by mass or more, 6.0×10³ parts by mass or more, 8.0×10³ parts by mass or more, 1.0×10⁴ parts by mass or more, 1.7×10⁴ parts by mass or more, 2.0×10⁴ parts by mass or more, 3.0×10⁴ parts by mass or more, 5.0×10⁴ parts by mass or more, or 6.0×10⁴ parts by mass or more, from the viewpoint of easily obtaining excellent antibacterial activity and antistatic property while suppressing stickiness and roughness.

The content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 1.0×10⁵ parts by mass or less, 8.0×10⁴ parts by mass or less, 6.0×10⁴ parts by mass or less, 5.0×10⁴ parts by mass or less, 3.0×10⁴ parts by mass or less, 2.0×10⁴ parts by mass or less, 1.7×10⁴ parts by mass or less, 1.0×10⁴ parts by mass or less, 8.0×10³ parts by mass or less, 6.0×10³ parts by mass or less, 5.0×10³ parts by mass or less, 4.4×10³ parts by mass or less, 4.0×10³ parts by mass or less, 3.0×10³ parts by mass or less, 2.2×10³ parts by mass or less, 2.0×10³ parts by mass or less, 1.1×10³ parts by mass or less, 1.0×10³ parts by mass or less, 7.0×10² parts by mass or less, 6.3×10² parts by mass or less, 6.0×10² parts by mass or less, 5.0×10² parts by mass or less, 4.4×10² parts by mass or less, 4.0×10² parts by mass or less, 3.0×10² parts by mass or less, 2.2×10² parts by mass or less, 2.0×10² parts by mass or less, or 1.1×10² parts by mass or less, from the viewpoint of easily obtaining excellent antibacterial activity and antistatic property while suppressing stickiness and roughness.

From these viewpoints, the content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 1.0×10² to 1.0×10⁵ parts by mass, 3.0×10² to 5.0×10⁴ parts by mass, 5.0×10² to 3.0×10⁴ parts by mass, 7.0×10² to 2.0×10⁴ parts by mass, or 1.0×10² to 1.0×10⁴ parts by mass.

The fiber for artificial hair of the present embodiment may have an ammonia component (excluding a component corresponding to the antistatic agent A) that is present in at least a part of the surface of the base fiber, or may not have such an ammonia component. By using the ammonia component, since the metal ion or the antistatic agent is likely to be present in at least a part of the surface of the base fiber (at the time of production of the fiber for artificial hair, the stability of a fiber treating agent described below is likely to be enhanced), excellent antibacterial activity and antistatic property are easily obtained while suppressing stickiness and roughness. Examples of the ammonia component include ammonia and ammonium cation (NH₄ ⁺). The ammonia component may exist as ammonium hydroxide.

The fiber for artificial hair of the present embodiment may have other additive (excluding a component corresponding to the metal ion A, the antistatic agent A, or the ammonia component) that is present in at least a part of the surface of the base fiber. Examples of such an additive include an antibacterial processing agent, a deodorant processing agent, an antifungal processing agent, a UV cutting agent, a softener, an SR processing agent, an aromatic processing agent, a flame retardant, an antifoaming agent, and fragrance. As the additive, an amine compound (for example, ethylenediaminetetraacetic acid (EDTA); excluding a compound corresponding to the antistatic agent), a silicone compound, an alkali metal, polyoxyethylene alkyl ether, or the like may be used. The amine compound may be a compound having a chelate effect. In the fiber for artificial hair of the present embodiment, the silicone compound may not be present in the surface of the base fiber. In the fiber for artificial hair of the present embodiment, at least one selected from the group consisting of zeolite and zirconium carbide may not be present in the surface of the base fiber, or the base fiber may not contain at least one selected from the group consisting of zeolite and zirconium carbide.

The metal ion A, the antistatic agent A, the ammonia component, and the additive mentioned above may be present at the mutually same place or at mutually different places on the surface of the base fiber, respectively. The fiber for artificial hair of the present embodiment may have a fiber treating agent (treating agent) that is present in at least a part of the surface of the base fiber or may be a fiber for artificial hair of which the surface is treated with a fiber treating agent.

The single fiber fineness of the fiber for artificial hair of the present embodiment is preferably in the following range after a stretching treatment. The single fiber fineness is preferably 20 decitex or more. The single fiber fineness is preferably 100 decitex or less. From these viewpoints, the single fiber fineness is preferably 20 to 100 decitex.

The fiber for artificial hair of the present embodiment may be obtained by bringing a base fiber into contact with a fiber treating agent (treating agent) containing the metal ion A and the antistatic agent A, or may be obtained by individually bringing respective components such as the metal ion A and the antistatic agent A into contact with a base fiber. As an example of a method for producing a fiber for artificial hair, a method for producing a fiber for artificial hair of the present embodiment includes a fiber treating step of bringing a base fiber into contact with a fiber treating agent (treating agent) containing the metal ion A and the antistatic agent A. The fiber treating agent may be a treatment liquid containing a liquid component such as water. The fiber treating agent may contain the ammonia component, the additive, or the like mentioned above, in addition to the metal ion A and the antistatic agent A.

The content of the metal ion A in the fiber treating agent is 3.0×10⁻⁴% by mass or more based on the total mass of the fiber treating agent from the viewpoint of obtaining excellent antibacterial activity. The content of the metal ion A in the fiber treating agent is 3.0×10⁻²% by mass or less based on the total mass of the fiber treating agent from the viewpoint of obtaining an excellent roughness suppressing effect of the fiber for artificial hair. That is, the content of the metal ion A in the fiber treating agent is 3.0×10⁻⁴ to 3.0×10⁻²% by mass based on the total mass of the fiber treating agent.

The content of the metal ion A, the content of the silver ion, the content of the zinc ion, or the content of the copper ion is preferably 5.0×10⁻⁴% by mass or more, 8.0×10⁻⁴% by mass or more, 9.0×10⁻⁴% by mass or more, 9.8×10⁻⁴% by mass or more, 1.0×10⁻³% by mass or more, 3.0×10⁻³% by mass or more, 5.0×10⁻³% by mass or more, 8.0×10⁻³% by mass or more, 1.0×10⁻²% by mass or more, 1.5×10⁻²% by mass or more, 2.0×10⁻²% by mass or more, or 2.5×10⁻²% by mass or more, based on the total mass of the fiber treating agent, from the viewpoint of easily obtaining excellent antibacterial activity.

The content of the metal ion A, the content of the silver ion, the content of the zinc ion, or the content of the copper ion is preferably 2.5×10⁻²% by mass or less, 2.0×10⁻²% by mass or less, 1.5×10⁻²% by mass or less, 1.0×10⁻²% by mass or less, 8.0×10⁻³% by mass or less, 5.0×10⁻³% by mass or less, 3.0×10⁻³% by mass or less, 1.0×10⁻³% by mass or less, or 9.8×10⁻⁴% by mass or less, based on the total mass of the fiber treating agent, from the viewpoint of easily obtaining excellent tactile sensation (such as a stickiness suppressing effect or a roughness suppressing effect) of the fiber for artificial hair.

The content of the metal ion A, the content of the silver ion, the content of the zinc ion, or the content of the copper ion is preferably 5.0×10⁻⁴ to 2.5×10⁻²% by mass, 9.0×10⁻⁴ to 2.5×10⁻²% by mass, 1.0×10⁻³ to 2.0×10⁻²% by mass, 5.0×10³ to 2.0×10⁻²% by mass, or 1.0×10⁻³ to 2.0×10²% by mass, based on the total mass of the fiber treating agent, from the viewpoint of easily achieving both the antibacterial activity and the tactile sensation at a high level.

The content of the antistatic agent A in the fiber treating agent is 0.005% by mass or more based on the total mass of the fiber treating agent from the viewpoint of obtaining excellent antistatic property. The content of the antistatic agent A in the fiber treating agent is 4% by mass or less based on the total mass of the fiber treating agent from the viewpoint of obtaining an excellent stickiness suppressing effect of the fiber for artificial hair. That is, the content of the antistatic agent A in the fiber treating agent is 0.005 to 4% by mass based on the total mass of the fiber treating agent.

The content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 0.01% by mass or more, 0.02% by mass or more, 0.05% by mass or more, 0.1% by mass or more, 0.15% by mass or more, 0.18% by mass or more, 0.19% by mass or more, 0.2% by mass or more, 0.3% by mass or more, 0.5% by mass or more, 0.8% by mass or more, 0.9% by mass or more, 1% by mass or more, 1.8% by mass or more, 2% by mass or more, 3% by mass or more, 3.5% by mass or more, or 3.6% by mass or more, based on the total mass of the fiber treating agent, from the viewpoint of easily obtaining excellent antistatic property.

The content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 3.6% by mass or less, 3.5% by mass or less, 3% by mass or less, 2% by mass or less, 1.8% by mass or less, 1% by mass or less, 0.9% by mass or less, 0.8% by mass or less, 0.5% by mass or less, 0.3% by mass or less, 0.2% by mass or less, 0.19% by mass or less, 0.18% by mass or less, 0.15% by mass or less, 0.1% by mass or less, 0.05% by mass or less, or 0.02% by mass or less, based on the total mass of the fiber treating agent, from the viewpoint of easily obtaining an excellent stickiness suppressing effect of the fiber for artificial hair.

From these viewpoints, the content of the antistatic agent A, the content of the cationic antistatic agent, or the content of the non-ionic antistatic agent is preferably 0.01 to 3.6% by mass, 0.02 to 3% by mass, 0.05 to 1% by mass, 0.1 to 0.8% by mass, 0.1 to 0.5% by mass, or 0.1 to 0.3% by mass, based on the total mass of the fiber treating agent.

In the case of using the fiber treating agent, the fiber treating agent can be applied to at least a part of the surface of the base fiber. In this case, a conventionally known means for applying a liquid to a fiber can be used. Examples thereof include a means for applying the fiber treating agent to the fiber for artificial hair by a roll having a surface to which the fiber treating agent has been attached (roll transfer method); a means for immersing the base fiber in a liquid tank storing the fiber treating agent; and a means for attaching the fiber treating agent to the base fiber with an applicator such as a brush and a paint brush.

The method for producing a fiber for artificial hair of the present embodiment may include a spinning step of spinning a composition containing a base fiber material to obtain a base fiber, before the fiber treating step. In the spinning step, the composition containing a base fiber material can be subjected to melt-spinning (melt-defornation).

The method for producing a fiber for artificial hair of the present embodiment may include a kneading step of melt-kneading a composition containing a base fiber material, before the spinning step. As an apparatus for performing melt-kneading, various general kneading machines can be used. Examples of the kneading machine include a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, and a kneader.

The method for producing a fiber for artificial hair of the present embodiment may include a stretching step of subjecting the fiber (unstretched fiber) obtained in the spinning step to a stretching treatment, before the fiber treating step.

From the viewpoint that the strength development of the fiber is likely to occur, the stretch ratio in the stretching step is preferably 1.5 times or more, and more preferably 2.0 times or more. From the viewpoint that fiber breakage is less likely to occur at the time of the stretching treatment, the stretch ratio is preferably 5.0 times or less, and more preferably 4.0 times or less. From these viewpoints, the stretch ratio is preferably 1.5 to 5.0 times, and more preferably 2.0 to 4.0 times.

The stretching treatment may be carried out by a two-step method in which an unstretched fiber is first wound on a bobbin and then stretched in a step that is not continuous with the spinning step, or may be carried out by a direct spinning stretching method in which an unstretched fiber is stretched in a step continuous with the spinning step without being wound on a bobbin. The stretching treatment may be carried out by a one-stage stretching method of performing stretching once to a desired stretch ratio or may be carried out by a multistage stretching method of performing stretching to a desired stretch ratio by two or more times of stretching.

The temperature of the stretching treatment is preferably 80° C. to 120° C. When the temperature is 80° C. or higher, the strength of the fiber is likely to be sufficiently secured and fiber breakage is less likely to occur. When the temperature is 120° C. or lower, a suitable tactile sensation of the fiber is likely to be obtained.

The method for producing a fiber for artificial hair of the present embodiment may include a heat treatment step of heat-treating (annealing) the fiber (stretched fiber) obtained in the stretching step, after the stretching step. By performing the heat treatment step, the thermal shrinkage rate of the stretched fiber can be decreased.

The heat treatment temperature is preferably 100° C. or higher and more preferably 120° C. or higher. The heat treatment temperature is preferably 200° C. or lower and more preferably 150° C. or lower. The heat treatment may be carried out continuously after the stretching treatment or may be carried out after a while after winding the stretched fiber once.

A headdress article of the present embodiment has the fiber for artificial hair of the present embodiment. The headdress article of the present embodiment is an article that is wearable on and removable from the head portion, and the headdress article may be an embodiment composed of the fiber for artificial hair of the present embodiment (for example, a fiber bundle of the fiber for artificial hair). Examples of the headdress article include hairpieces, hair wigs, hair pieces, braid, hair extension hair, and attached hair.

EXAMPLES

Hereinafter, the present invention will be more specifically described by way of Examples; however, the present invention is not intended to be limited to these Examples. Hereinafter, a notation such as “1.0E-03” or “1.0E+10” means “1.0×10⁻³”, “1.0×10¹⁰”, or the like.

<Preparation of Base Fiber>

The following base fibers shown in Tables 1 to 4 were prepared.

Base fiber A: Vinyl chloride-based fiber, a fiber using polyvinyl chloride (TAIYO VINYL CORPORATION, trade name “TH-700”), a fiber spun from a nozzle having an outlet cross-section with a cross-sectional secondary moment of the weak axis of 10×10⁻⁴ mm⁴ (a fiber produced by a solution spinning method), average fineness 40 to 70 decitex (average value of fineness of 100 fibers)

Base fiber B: Fiber of a copolymer of vinyl chloride and acrylic acid ester, a fiber spun from a nozzle having an outlet cross-section with a cross-sectional secondary moment of the weak axis of 10×10⁻⁴ mm⁴ (a fiber produced by a solution spinning method), average fineness 40 to 70 decitex (average value of fineness of 100 fibers) Base fiber C: Polypropylene fiber, a fiber spun from a nozzle having an outlet cross-section with a cross-sectional secondary moment of the weak axis of 10×10⁻⁴ mm⁴ (a fiber produced by a melt-spinning method), average fineness 40 to 70 decitex (average value of fineness of 100 fibers)

Base fiber D: PET fiber, a fiber spun from a nozzle having an outlet cross-section with a cross-sectional secondary moment of the weak axis of 10×10⁻⁴ mm⁴ (a fiber produced by a melt-spinning method), average fineness 40 to 70 decitex (average value of fineness of 100 fibers)

<Preparation of Fiber Treating Agent>

The fiber treating agent was prepared by mixing components (such as a metal ion source, an antistatic agent, and ammonium water) shown in Tables 1 to 4. The following reagents were used as components shown in each table.

(Metal Ion Source)

Metal ion source A (Ag): In-house preparation, a silver nitrate aqueous solution containing 0.1% by mass of silver ion

Metal ion source B (Zn): In-house preparation, a zinc nitrate aqueous solution containing 0.1% by mass of zinc ion

Metal ion source C (Cu): In-house preparation, a copper nitrate aqueous solution containing 0.10% by mass of copper ion

Metal ion source D (Ag): DuPont, trade name “SILVADUR 930 Flex Antimicrobial”, an aqueous dispersion containing a silver ion, ammonium hydroxide, and a polymer (silver ion amount: 0.098% by mass, ammonium hydroxide amount: 0.25 to 1.0% by mass, polymer: a copolymer having a structural unit derived from 1-vinylimidazole and a structural unit derived from poly(ethylene glycol) methyl ether methacrylate (a polymer compound forming a composite body with a silver ion))

(Antistatic Agent)

[Cationic Antistatic Agent]

Cationic antistatic agent A: YOSHIMURA OIL CHEMICAL Co., Ltd., trade name “GST-8”, an aqueous solution containing 20% by mass of a guanidine hydrochloride salt

Cationic antistatic agent B: In-house preparation, an aqueous solution obtained by diluting trade name “CATIOGEN TML” available from DKS Co. Ltd. with water (an aqueous solution containing 20% by mass of tetraalkylammonium chloride (a quaternary ammonium chloride aqueous solution))

Cationic antistatic agent C: In-house preparation, an aqueous solution obtained by diluting trade name “CATIOGEN ES-O” available from DKS Co. Ltd. with water (an aqueous solution containing 20% by mass of a tetraalkylammonium sulfate salt (a quaternary ammonium sulfate salt aqueous solution))

[Non-Ionic Antistatic Agent]

Non-ionic antistatic agent A: In-house preparation, an aqueous solution containing 20% by mass of polyethylene glycol having a weight average molecular weight of 550 to 650 (YOSHIMURA OIL CHEMICAL Co., Ltd., trade name “PEG-600”)

Non-ionic antistatic agent B: YOSHIMURA OIL CHEMICAL Co., Ltd., trade name “TYO-11”, an aqueous solution containing 20% by mass of a copolymer of propylene oxide and ethylene oxide

[Anionic Antistatic Agent]

In-house preparation, an aqueous solution obtained by diluting trade name “Antox EHD-PNA” available from NIPPON NYUKAZAI CO., LTD. with water (an aqueous solution containing 20% by mass of a polyoxyalkylene alkyl ether phosphate salt (a phosphate anion salt aqueous solution))

(Ammonium Water)

FUJIFILM Wako Pure Chemical Corporation, trade name “Ammonia Solution”, an ammonia aqueous solution containing 25% by mass of ammonia

<Stability of Fiber Treating Agent>

The presence and absence of deposition in the fiber treating agent were checked by visual confirmation and evaluation was performed based on the following criteria. Specifically, the fiber treating agent was stirred and then left to stand still, and the presence and absence of deposition in room temperature were checked. The results are shown in Tables 1 to 4.

A: The deposition was not formed in one week or longer.

B: The deposition was formed in one day or longer and shorter than one week.

C: The deposition was formed in half a day or longer and shorter than one day.

D: The deposition was formed in shorter than half a day.

<Production of Fiber for Evaluation>

The above-mentioned base fiber was stretched at 100° C., and then the above-mentioned fiber treating agent was applied to the base fiber by a roll transfer method. As roll transfer conditions, the radius of the roll was 125 mm, the roll was immersed in the fiber treating agent with a height of 20 mm from the lower end of the roll, and the roll rotation speed was 8 m/min. Thereafter, annealing was performed at 120° C., and a fiber for evaluation (fiber for artificial hair) having a single fiber fineness of 20 to 100 decitex was obtained. The stretch ratio was 3.25 times, and the relaxation ratio during annealing was 25%. The relaxation ratio during annealing is a value calculated by the formula: “(Circumference of the outlet nearest portion of the roller of the annealing furnace)/(Circumference of the inlet nearest portion of the roller of the annealing furnace)”.

The amounts (unit: % by mass) of the metal ion and the antistatic agent attached to the surface of the fiber for evaluation are shown as the contents of active ingredients in the fiber for evaluation in each table. Assuming that the solid content in a decrement of the fiber treating agent is attached to the surface of the fiber for evaluation, the attached amount was calculated by the formula: “((Decrement of the fiber treating agent in the fiber treating step×(Active ingredient ratio [%] of each reagent in the fiber treating agent/100))/Total amount of the fiber for evaluation)×100”.

<Evaluation>

The antibacterial activity, the antistatic property, the tactile sensation, and the flame retardation were evaluated using the above-mentioned fiber for evaluation. The results are shown in Tables 1 to 4.

As shown in each table, it is found that, in Examples, excellent antibacterial activity and antistatic property are obtained while suppressing stickiness and roughness.

(Antibacterial Activity)

The antibacterial activity of the fiber for evaluation was evaluated based on JIS L 1902. Staphylococcus aureus was used as a test bacterium, and the antibacterially active value (difference in the number of viable bacteria) before and after the bacteria was left to stand at 37° C. for 18 hours was measured. The “antibacterially active value” is the following value defined in “Bacterial-liquid absorption method” of JIS L 1902.

A=(logC_(t)−logC₀)−(logT_(t)−logT₀)

-   -   A: antibacterially active value     -   C_(t): arithmetic average common logarithm of the respective         numbers of viable bacteria in three specimens of each of the         target samples after cultivation for 18 hours     -   C₀: arithmetic average common constant of the respective numbers         of viable bacteria in three specimens of each of the target         samples immediately after inoculation     -   T_(t): arithmetic average common logarithm of the respective         numbers of viable bacteria in three specimens of each of the         test samples after cultivation for 18 hours     -   T₀: arithmetic average common logarithm of the respective         numbers of viable bacteria in three specimens of each of the         test samples immediately after inoculation

(Antistatic Property)

The above-mentioned fibers for evaluation were bundled to obtain a fiber bundle having a length of 250 mm and a mass of 20 g. Subsequently, the fiber bundle was left to stand for 24 hours in the environment of 23° C. and 50% RH, and then the surface resistance value was measured under the condition of an applied voltage of 10 V using a digital ultra-high resistance/micro current meter (ADVANTEST CORPORATION, trade name: R8340). The antistatic property was evaluated based on an average value of five times measurements. The average value is shown in each table.

(Tactile Sensation)

The stickiness and the roughness were evaluated as the tactile sensation. The above-mentioned fibers for evaluation were bundled to obtain a fiber bundle having a length of 250 mm and a mass of 20 g. The stickiness and the roughness of the fiber bundle were evaluated based on the following criteria by touching of ten technicians for treatment of the fiber for artificial hair (work experience: 5 years or longer). A case where even one person evaluating as “NG” existed was determined as “NG”, and in a case where there was no NG evaluation, the total score was calculated. The total score is shown in each table.

[Stickiness]

-   -   3: There is no stickiness.     -   1: There is stickiness within an acceptable range.

NG: There is stickiness that is not acceptable.

[Roughness]

-   -   3: There is no roughness.     -   1: There is roughness within an acceptable range.

NG: There is roughness that is not acceptable.

(Flame Retardation)

The above-mentioned fibers for evaluation were bundled to obtain ten fiber bundles having a length of 200 mm and a mass of 1 g. Subsequently, the fiber bundles were left to stand for 24 hours in the environment of 23° C. and 50% RH. Thereafter, the fiber bundles were exposed to fire for 3 seconds using an igniter (Tokai Co., trade name: CR Chakkaman), and whether or not the fire is spontaneously extinguished was checked. Determination was made based on the following criteria.

-   -   A: The fire is extinguished in all of the ten fiber bundles.     -   B: The fire is extinguished in one to nine fiber bundles.     -   C: The fire is not extinguished in all of the fiber bundles.

TABLE 1 Example 1 2 3 4 5 6 7 8 9 Base fiber A A A A A A A A A Blending amount Metal ion  1 15 25 [parts by mass] source A (Ag) Metal ion  1 15 25 source B (Zn) Metal ion  1 15 25 source C (Cu) Cationic antistatic  1  1  1  1  1  1  1  1  1 agent A Water 98 84 74 98 84 74 98 84 74 Content in fiber Metal ion  1.0E−03  1.5E−02  2.5E−02  1.0E−03  1.5E−02  2.5E−02  1.0E−03  1.5E−02  2.5E−02 treating agent Antistatic agent  0.2  0.2  0.2  0.2  0.2  0.2  0.2  0.2  0.2 [% by mass] Stability of fiber treating agent B B B B B B B B B Content in fiber Metal ion  3.0E−04  4.5E−03  8.0E−03  3.0E−04  4.5E−03  8.0E−03  3.0E−04  4.5E−03  8.0E−03 for evaluation Antistatic agent  0.05  0.05  0.05  0.05  0.05  0.05  0.05  0.05  0.05 [% by mass] Antibacterial Antibacterially  4.0 ≥5.0 ≥5.0  2.2  2.8  4.0  2.5  3.1  4.3 activity active value Antistatic Surface resistance  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10 property value [Ω] Tactile Stickiness 26 26 26 26 26 26 26 26 26 sensation Roughness 26 22 14 26 22 14 26 22 14 Flame retardation A A A A A A A A A

Comparative Example Example 10 11 12 13 14 15 16 1 2 Base fiber A A A A B C D A A Blending amount Metal ion source A 15 15 15 15  0.1 35 [parts by mass] (Ag) Metal ion source D  1 15 25 (Ag) Cationic antistatic  1  1  1  1  1  1  1  1  1 agent A Ammonia solution  1.5 Water 98 84 74 84 84 84 84 98.9 64 Content in fiber Metal ion  9.8E−04  1.5E−02  2.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.0E−04  3.5E−02 treating agent Antistatic agent  0.2  0.2  0.2  0.197  0.2  0.2  0.2  0.2  0.2 [% by mass] Stability of fiber treating agent A A A A B B B B B Content in fiber for Metal ion  3.0E−04  4.5E−03  8.0E−03  4.5E−03  4.5E−03  4.5E−03  4.5E−03  3.0E−05  1.2E−02 evaluation [% by mass] Antistatic agent  0.05  0.05  0.05  0.9  0.05  0.05  0.05  0.05  0.05 Antibacterial activity Antibacterially active  4.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0  1.5 ≥5.0 value Antistatic property Surface resistance  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10  1.0E+10 value [Ω] Tactile sensation Stickiness 26 20 14 26 26 26 26 26 26 Roughness 26 22 14 26 26 26 26 30 NG Flame retardation A A A A A B B A A

TABLE 3 Example 17 18 19 20 21 22 23 24 Base fiber A A A A A A A A Blending amount Metal ion source A (Ag) 15 15 15 15 15 15 15 15 [parts by mass] Cationic antistatic agent A  0.1 18 Cationic antistatic agent B  0.1  1  4.5 Cationic antistatic agent C  0.1  1  4.5 Water 84.9 67 84.9 84 80.5 84.9 84 80.5 Content in fiber treating Metal ion  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02 agent Antistatic agent [% by mass]  0.02  3.6  0.02  0.2  0.9  0.02  0.2  0.9 Stability of fiber treating agent B B B B B C C C Content in fiber for Metal ion  4.5E−03  4.5E−03  4.5E−03  4.5E−03  4.5E−03  4.5E−03  4.3E−03  5.0E−04 evaluation [% by mass] Antistatic agent  0.005  0.9  0.02  0.2  0.9  0.02  0.19  0.3 Antibacterial activity Antibacterially active value ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0  4.2 Antistatic property Surface resistance value [Ω]  1.0E+11  5.0E+08  1.0E+11  1.0E+10  5.0E+08  1.0E+11  1.0E+10  3.0E+10 Tactile sensation Stickiness 30 16 30 26 16 30 26 24 Roughness 22 22 22 22 22 22 22 22 Flame retardation A A A A A A A A

TABLE 4 Example Comparative Example 25 26 27 28 29 30 3 4 5 Base fiber A A A A A A A A A Blending amount Metal ion source A 15 15 15 15 15 15 15 15 15 [parts by mass] (Ag) Cationic antistatic  0.01 22 agent A Non-ionic antistatic  0.1  1  9 agent A Non-ionic antistatic  0.1  1  9 agent B Anionic antistatic  1 agent Water 84.9 84 76 84.9 84 76 84.99 63 84 Content in fiber Metal ion  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02  1.5E−02 treating agent Antistatic agent  0.02  0.2  1.8  0.02  0.2  1.8  0.002  4.4  0.2 [% by mass] Stability of fiber treating agent B B B B B B B B D Content in fiber for Metal ion  4.5E−03  4.5E−03  4.5E−03  4.5E−03  4.5E−03  4.5E−03  4.5E−03  4.5E−03  5.0E−05 evaluation Antistatic agent  0.01  0.1  0.9  0.01  0.1  0.9  0.0005  1.3  0.0007 [% by mass] Antibacterial Antibacterially active ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 ≥5.0 <2.0 activity value Antistatic Surface resistance  1.0E+12  5.0E+11  1.0E+11  1.0E+12  5.0E+11  1.0E+11  1.0E+13  4.0E+08  8.0E+12 property value [Ω] Tactile sensation Stickiness 28 26 16 28 26 16 30 NG 30 Roughness 22 22 22 22 22 22 22 22 22 Flame retardation A A A A A A A A A 

1. A fiber for artificial hair, comprising: a base fiber; a metal ion; and an antistatic agent, wherein the metal ion and the antistatic agent are present in at least a part of a surface of the base fiber, the metal ion is at least one selected from the group consisting of a silver ion, a zinc ion, and a copper ion, a content of the metal ion is 5.0×10⁻⁵% to 1.0×10⁻²% by mass based on the total mass of the fiber for artificial hair, the antistatic agent is at least one selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent, and a content of the antistatic agent is 0.001 to 1% by mass based on the total mass of the fiber for artificial hair.
 2. The fiber for artificial hair according to claim 1, wherein the base fiber contains a vinyl chloride-based resin.
 3. The fiber for artificial hair according to claim 1, wherein the base fiber contains a polyester-based resin.
 4. The fiber for artificial hair according to claim 1, wherein the base fiber contains a polyolefin-based resin.
 5. The fiber for artificial hair according to claim 1, wherein the metal ion includes a silver ion.
 6. The fiber for artificial hair according to claim 1, wherein the antistatic agent includes at least one selected from the group consisting of a quaternary ammonium salt and a guanidine compound.
 7. The fiber for artificial hair according to claim 1, wherein the antistatic agent includes at least one selected from the group consisting of polyalkylene glycol and a copolymer of propylene oxide and ethylene oxide.
 8. The fiber for artificial hair according to claim 1, wherein at least one selected from the group consisting of the cationic antistatic agent and the non-ionic antistatic agent includes an antistatic agent not containing a sulfur atom.
 9. The fiber for artificial hair according to claim 1, further comprising an ammonia component that is present in at least a part of the surface of the base fiber.
 10. A headdress article comprising the fiber for artificial hair according to claim
 1. 11. A method for producing a fiber for artificial hair, the method comprising a step of bringing a base fiber into contact with a treating agent containing a metal ion and an antistatic agent, wherein the metal ion is at least one selected from the group consisting of a silver ion, a zinc ion, and a copper ion, a content of the metal ion is 3.0×10⁻⁴% to 3.0×10⁻²% by mass based on the total mass of the treating agent, the antistatic agent is at least one selected from the group consisting of a cationic antistatic agent and a non-ionic antistatic agent, and a content of the antistatic agent is 0.005 to 4% by mass based on the total mass of the treating agent.
 12. The fiber for artificial hair according to claim 1, wherein the metal ion includes a zinc ion.
 13. The fiber for artificial hair according to claim 1, wherein the metal ion includes a copper ion.
 14. The fiber for artificial hair according to claim 1, wherein the antistatic agent includes a cationic antistatic agent.
 15. The fiber for artificial hair according to claim 1, wherein the antistatic agent includes a non-ionic antistatic agent.
 16. The method for producing a fiber for artificial hair according to claim 11, wherein the metal ion includes a silver ion.
 17. The method for producing a fiber for artificial hair according to claim 11, wherein the metal ion includes a zinc ion.
 18. The method for producing a fiber for artificial hair according to claim 11, wherein the metal ion includes a copper ion.
 19. The method for producing a fiber for artificial hair according to claim 11, wherein the antistatic agent includes a cationic antistatic agent.
 20. The method for producing a fiber for artificial hair according to claim 11, wherein the antistatic agent includes a non-ionic antistatic agent. 